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Sleepiness at the Wheel
One of the leading invisible causes of road accidents. Reduced vigilance impairs reflexes and decision-making in ways that laboratory studies have compared to alcohol - yet cannot be measured at accident scenes.
Last revision: 19.07.2026
| 19.07.2026 | OG image redrawn in the series style |
Up to 30% of serious accidents in evening and night hours are linked to sleepiness (Prof. Mauro Manconi, EOC).
The brain drifts out of wakefulness gradually. Microsleeps lasting a few seconds appear, and lane-keeping deteriorates. You can usually feel sleepiness coming: in a driving simulator, young drivers coming off a short night never fell asleep without first feeling it build for a long time (Reyner and Horne 1998, DOI 10.1007/s004140050131). The risk is not giving it the weight it deserves.
Unlike alcohol, sleepiness has no breathalyser. It leaves no measurable trace at accident scenes. This forensic gap is one of the core problems Drive Awake addresses.
In the Quinto case (A2, 2016), an experienced driver had severe obstructive sleep apnoea, diagnosed after the crash. The criminal proceedings ended in an acquittal, which implies no broader conclusion about what happened. Sleep apnoea can be diagnosed with a sleep study; what is still missing today is a roadside test for sleepiness.
